The present invention relates to slot machines and, in particular, to slot machines of the type in which a microcomputer determines occurrence patterns of combinations of different symbols visible through windows of a machine housing so as to pay out coins or tokens as prizes according to patterns of prize-winning combinations of symbols.
In slot machines, a plurality of reels, for instance three reels rotatably arranged side by side are caused to stop, individually, when stop buttons associated with the respective reels, are pushed or after a proper lapse of time predetermined by random timer means. Three symbols of each reel are visible through a window. The machine can award coins or tokens as prizes when predetermined prize-winning combinations of symbols occur in at least one of three transverse and two diagonal rows, five rows in total, which are prize-awarding rows. The number of prize coins or tokens to be paid out is according to the occurrence patterns of the combinations of symbols. However, the number of prize-awarding rows which are available is increased according to the number of coins or tokens inserted. For example, only the middle transverse row may be available for a single coin or token. Thus the chances of enjoying a prize-winning combination of symbols are improved in dependence on the number of coins or tokens inserted.
In conventional slot machines, the respective reels are provided with symbol detection brush members, three for every reel. This leads to an intricate construction of the machines and to failures of the machines owing to this intricate construction. Such slot machines are further designed in such a way that short circuits including the brush members associated with the respective reels determine occurrence patterns of the combinations of symbols and cause a circuit element to be active so as to pay out a given number of coins or tokens as prizes. Since, however, the pattern-determining and prize-paying-out device has a large number of relay devices, such a device is undesirable in view of high cost and low reliability.